Overview
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Port Security
This section describes the Port Security feature.
Overview
Port Security:
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Allows for limiting the number of MAC addresses on a given port.
•
Packets that have a matching MAC address (secure packets) are forwarded; all other pack-
ets (unsecure packets) are restricted.
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Enabled on a per port basis.
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When locked, only packets with allowable MAC address will be forwarded.
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Supports both dynamic and static.
•
Implement two traffic filtering methods. These methods can be used concurrently.
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Dynamic Locking - User specifies the maximum number of MAC addresses that can
be learned on a port. After the limit is reached, additional MAC addresses are not
learned. Only frames with an allowable source MAC address are forwarded.
-
Static Locking - User manually specifies a list of static MAC addresses for a port.
Dynamically locked addresses can be converted to statically locked addresses.
Operation
Port Security:
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Helps secure network by preventing unknown devices from forwarding packets.
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When link goes down, all dynamically locked addresses are ‘freed.’
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If a specific MAC address is to be set for a port, set the dynamic entries to 0, then only
allow packets with a MAC address matching the MAC address in the static list.
•
Dynamically locked MAC addresses are aged out if another packet with that address is not
seen within the age-out time. The user can set the time-out value.
•
Dynamically locked MAC addresses are eligible to be learned by another port.
•
Static MAC addresses are not eligible for aging.
•
Dynamically locked addresses can be converted to statically locked addresses.
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